Leather Stiffening

[tankerman1967]

Hey yall

Just a quick question. What is the best way to stiffen leather? I have some 2-3 Oz leather and am about to start doing some pouches. I need to stiffen the bag part. Not rock hard but hard. Any ideas??

Thanks

[sharkeyfinn]

hi, the only thing i can think of is to dampen it and then bake it, put it in the oven on a very low heat and check every ten mins. hope this helps ;-)

[papaw]

Use heat wet leather if it is just certain areas you can use hair drier just not too hot if using over 170 is about as low as they will go.

[snubbyfan]

To stiffen leather for a holster, I just use hot tap water for molding. It's 8-9 ounce so I'm not sure how that'll work with 2-3 ounce. I'm reluctant to put it in an oven or use a hair dryer on it for fear of drying it out.

[Tiara]

http://www.goodsjapan.com/leather-hardeners-36-c.asp

I've used the water based product a few times with good results. no bad odor didn't darken even white deerskin when dried yet did harden enough to hold a scrunched up test shape and still flex.

I am also trying a few other ways to harden leather. Did a dip of several types of leather in warm water with ammonia until bubbles stopped rising, then wrapped around some jars/cans and used vet wrap to hold until dried. 2 were still damp the next day and placed in low oven for about an hour still on the molds. an oil tanned leather held well quite stiff but flexed enough the idea may work for some cuffs. the veg tan didn't harden as much and the deerskin, same type as used with the commercial product, didn't change much at all.

One guy who has a lot of youtube videos on leather, think he's in england, did a review of the leather products from this site. overall very positive. I think he mentioned that japan is strict on chemical toxins in consumer products and nothing on the site had much of a warning. I don't know what is in it but it did work, didn't stink and the small bit I got on my hands didn't cause any irritation

[tankerman1967]

I did try to heat it in the oven after wetting the first. Kinda scorched it an shrunk it a bit. Also tried fabric stiffer, not that great on this thin leather. I read somewhere on using wood hardner. Gonna get some and try it. Will let yall know.

[Grey Drakkon]

A hair dryer gives you a lot more control over heating the leather, since you can hold it whatever distance works best. As long as you pay attention you won't scorch or shrink the leather.

[BDAZ]

Usually drying wet formed products i the sun is no problem but every once in a while I have a larger order and it rains! I have a fron load tryer which came with a rack for drying objects like shoes. When sun drying mt items will reach 140F which I find ideal. I use the very low heat setting in the dryer and it works perfectly.

Tiara: never use ammonia on leather!! Those bubbles you saw were a natural reaction to the acids in the leather which are critical for longevity.

Cya!

Bob

[Tiara]

Tankerman I don't think you've ever dried jerky in an oven. It requires just the lowest setting which may be as low as 120-150F and temps will be higher near the top than the lower racks.

Drakkon, the hair dryer tip is one of the things I'll be experimenting with later today or tomorrow. A friend has asked for a cuff in a lovely pale blue baby gator back and would like it asymmetrical and formed so it doesn't slip around much. Her wrist is close in size and shape to mine. I plan on trying some thin veg tan shaped to my wrist. Hoping to get it rigid enough to use without a metal cuff inside. Grain side towards the arm, flesh to flesh for gluing. The gator is pretty enough that stitching would detract from it. If that works, I'm thinking of trying for spiral armlets that way. Will get your samples sent out soon. The last thing I was waiting for came in.

Bob, the dilute ammonia method is mentioned several times on the board. Your comment brought up several points. One discussion on using ammonia indicated that this worked by lifting oils out and that alcohol would do the same. But I did wonder about the long term affects of an alkali on the leather. As it was quite dilute, I think its 1 part ammonia to 8 parts water, and enough long time members were mentioning it, it was worth a try. And with ammonia/urine having a long history in leather making, didn't seem too likely to be a problem. I play the Irish bodhran hand drum. One method of treating the drum skins is to bury it in a manure pile for a while. Those skins are supposed to play nicely if you can stand to do so before the stink dissipates. I had wondered about the chemistry of the ammonia method. As I started to dig around I found this link http://www.personal.utulsa.edu/~marc-carlson/leather/hl.html and http://www.leatherchemists.org/forum/forum_posts.asp?TID=230&KW=stiffening

The bubbling might be due to a chemical reaction but at such a low dilution I'm more likely to think it was simply due to the bubbling out of air as several references to soaking leather or drum skins state to soak until all bubbling stops to be cure it is saturated.

The question of being careful what we use on leather is important to long term results. Acid/alkaline balance, oils/fats that oxidize, dyes that may not take--http://www.dharmatrading.com/cgi-bin/search.cgi?query=reactive or http://www.dharmatrading.com/dyes/dharma-acid-dyes.html?lnav=dyes.html but there is mention that these dyes are sometimes used on leather.
I'd be cautious of using a product made for wood on leather without having heard from those with more experience or a good idea of any differences in the chemicals.
I'm thinking of trying this http://www.amazon.com/gp/product/B002BWF5PK/ref=ox_sc_act_title_4?ie=UTF8&psc=1&smid=ATVPDKIKX0DER#product-description-iframe as it is non corrosive and moisture curing. What? a low stink flexible adhesive that will cure faster in higher humidity? Hmm, what if I could take 2 pieces of leather I want to adhere, mist with water, spread this stuff on them, slap them together and align, wrap or clamp together and let sit for a few days? It might be worth the wait.
I might sign on the leatherchemists forum to ask if there is a chance this stuff might not be wise down the line.

[BDAZ]

Good point about the air bubbles. I occasionally use vinageroon and neutralize with baking soda and it is definitely CO2, not air I see. A test would be to soal the leather in water, drain and then apply the ammonia...bubbles = CO2 = PH Change.

BTW I used to build bodhrans when I lived in Ireland. I buried the fresh skins in alum for a couple of weeks and the trick it to apply the wet skins to the rim. After drying once they are never the same. (I also play Irish tenor and and on my way to a session this afternoon)

As for glues, try one of the polyurethanes, which is moisture activated. I have never used it on leather but I imagine it would work well for for certain applications, not as flexible as RTV but it will penetrate and expand.

Cya!

Bob

[Tiara]

Enjoy the session. I don't get to Celtic sessions often, the closest is an hour away now. Have done a couple of gigs with Irish music at a new pub we're hoping will start sessions. Do more playing of bluegrass, various world music, rock, whatever. It's a versatile drum. Even in the 4 years since I started with it, the drum makers have improved the skins, tuning rings, tuners, using just about anything from kangaroo to bison and drummers have added to the techniques of play, And must not forget the tipper makers! Another whole area combining old and new. Different woods, shape, length, counterweights, ah! data junkie heaven!

I've got a used bass drum skin I want to try to stencil and dye and then send to a fairly new bodhran maker in the US turning out some good drums. Haven't had the time yet to work out how to prevent the wicking I've had. I suspect an airbrush will be the way to go but don't have one and already have more I want to learn than I have time for.

I'm not sure if it is a moisture cure or not. I've been using a clear urethane called Liquid Fusion with good results. I'm interested in the silicone as a way to have some raised sections with flex and possibly try for my own cell phone case with an exotic leather covered in a clear material that will help absorb impact. Not sure if the flexible UV cure resins would be protective enough.

[BDAZ]

Not sure what pat of the world you are in. I'm currently in North Carolina and we have two sessions a week, same as Tucson, where I host one. I also play old time banjo and lots of jams here and Tucson as well.

I shot this a couple of years ago.

https://www.youtube.com/watch?v=xUMc8WIht4w

Cya!

Bob

Edited December 28, 2014 by BDAZ

[Itch]

This may work for you http://leatherworker.net/forum/index.php?showtopic=33257

[TwinOaks]

For the simple molding of leather, you could try the cuir bouilli method....which is 'wet forming'. The idea behind heating the leather is to speed up the drying and 'heat set' the collagen in the hide. I use a toaster oven set at 150, but with the door left open a little bit. Starting from 'cold', I set it for 10 min and start checking it at 6. If it's getting too hot to touch, it's time to pull the leather from the heat.

Another method you could use is to shape the leather as above, then coat the leather with a combination of melted wax and oil. When the leather and wax blend are hot, the leather will soak up the blend quite readily. Then when it cools, it will have a very hard hand and be very water resistant. This is often seen in traditional styled Puuko sheathes made from leather (as opposed to the fiber board they also use), and in some leather tankards, bottles, etc.

[tankerman1967]

Hey yall. I was at lowes the other day and saw this rotten wood stabilizer. I got it and gave it a try. I put one cote on the flesh side and let it dry overnight. The leather did stiffen up a bit. It also shrunk in thickness a bit also. The leather is still pliable and it retains its shape, for the most part. I think I am going to try tooling a test piece and put 2 layers of this on the flesh side. So far I think this will work for what I want. just stiff enough to hold a shape but not rock hard. I will keep yall updated on progress. I am also gonna try something from minwax called "wood hardener"

Thanks for all yall's time

I was trying to post a picture but the site will not let me. I will start a new thread when I get the test piece done

[BDAZ]

I am not at home or I'd test it first but if wet forming isn't sufficient, try "pasting" the flesh side with a standard water based wood glue. It is a service offered by some leaher suppliers.

Cya!

Bob

[Lillian ADju]

Hi
You have here an excellent tutorial
https://www.youtube.com/watch?v=lGikTadTN64

Regards
Aleksandar

[JoeSnuffie]

Maybe this would work on a larger scale. I use Mop and Glow 50/50 with water for the holes I make for bracelets that use Sam Brown studs or beads. I soak the flesh side around the hole and when it's dried it's almost as stiff as plastic and the stud or bead fits securely in with a nice snap. I'm wearing a 2 year old bracelet that still snaps in place.

[Tiara]

Joe, isn't the mop n glow the same basic ingredient as acrylic finish?

I tried that once but the stink from something in it gives me a bad chemical sensitivity reaction. I don't get that from

the acrylic leather finishes. Don't know if it is some sort of perfume added or what but it's nasty. I've had to leave the gym a few times when the hallway floor was being waxed with it.

But if its the same chemicals, soaking the flesh side and edges with acrylic leather finish should have the same effect.

[BDAZ]

After comparing the ingredients of mop & Glo and Resolene, it appears Mop & Glo has a much higher percntage of Acrylic polymers but it also contains a high percentage of Diethylene glycol monoethyl ethers, which is a solvent and used for the cleaning side of the product. I am not sure what affect it would have on undyed leather but would probably affect any oil or alcohol stains applied.

Cya!

Bob